Stave - Electrical Break
Richard FrenchThe University of Sheffield
Material from the ATLAS SCT/IBL/PIXEL community
ID gas barrier
Pixel detector EC SCT Barrel SCT
PP0
PPF1
PP1b
PP1a
PPB1
PPF0
PPB0
Distribution racks (PP3)
PP2b
PP2a at cryostat flange
Z = 0
Along Tile Calorimeter Barrel
Platform #7 or #1 level
R=1300 mm Z=3330 mm
R=2000 mm Z=3550 mm
R=2775 mm Z=3450 mm
R=4240 mm Z=2900 mm
Distance from PPF1 to PP2b – 220+700+100+775+550+1465=3810 mm=3.8 m
Heat exchanger
Heater
ID gas barrier
Pixel detector EC SCT Barrel SCT
PP0
PPF1
PP1b
PP1a
PPB1
PPF0
PPB0
Z = 0 Heat exchanger
Heater
Figure 1: Location of cooling components and external pipe destinations in ATLAS [Error! Bookmark not defined.,1]. [1] Pierre Bonneau, Technical Specification, Evaporative Cooling System for ATLAS Inner Detector
Silicon Trackers (Pixel and SCT): external part, WORK UNIT 1 . ATC-TL-EP-0001, EDMS N°391168
Location of cooling components and pipe destinations in ATLAS
Services routing of current ID from PP2
• How much of the wheel needs reinventing?
• Can we tweak an existing design?
• For reference – is the positional terminology the same?
Existing ATLAS layout and terminology to jog memory
• Electrical break on barrel was done with Beryllia. • Cooling pipe was copper-nickel.
• Upgrade uses Titanium as a baseline for Stave core.• CuNi was used for on detector pipework
• Do we have a baseline (CP2 Ti)?• Stainless steel (austenitic) was used for off detector
• What is our baseline? 316L?• C106 soft annealed copper was also used in small
amounts for manufacture of Heat Exchangers (HEX), S bends and other short lengths of tube both on and off detector• Not ideal.
• Unfilled PEEK tube (specially made 12mm ID 13mm OD) was used for gas ‘guidance’ of N2 dry gas around the detector.• Not thought about yet for N2 delivery.
Existing materials used in ATLAS SCT cooling system
Items to consider before addressing design of electrical break connectorGALVANIC STABILITY OF THE SYSTEM
ITE
Disc 1
Cu-Kapton (or Al-Kapton) Aluminsed Kapton Carbon fibre Foam Services Cu-Kapton (or Al-Kapton) tab or Litz wire
Disc 9
Module
Module
Shunt Shield
Shunt Shield
Thermal Pad
Support Pad
Wiggly Tape
PPF0/e
Support Cylinder
OTE
Front Support
Rear Membrane
Front Membrane
Cooling Pipe
LMT Insulating Break Ground
Sheet
STFT
PPF0/c
Grounding Foil
Cooling Interconnect
Rear Support
physical contact
connect to RCT
End-cap G&S Version 1.6 5/9/06
Rail
Disc Fixation
EC-A See Note Error! Reference source not found.
EC-C See Note Error! Reference source not found.
Endcap disks have ground referencing tapes that bond together the complex cooling tube paths.
SCT Endcap Grounding and Shielding Scheme
https://indico.cern.ch/getFile.py/access?contribId=5&resId=0&materialId=slides&confId=206624
Life gets much simpler with the current proposal from Ned.
• Location of electrical break does not matter so either at • PPB0
Or• PPB???? 1ish.
• Decided at RAL meeting to concentrate at end of Stave option.• Mass implication?• Materials choice• CRITICAL JOINT• Encapsulate connector
at end of Stave• OD???• Diameter
transition
Quick peek at IBL progress
• 3 connector types• Brazed union• De-mountable connector with swaged tube• Electrical break (brazed ceramic)• OD crucial to encapsulation in Stave.• Conductivity with carbon fibre skins
IBL Electrical Break and Connectors
2.5 to 1.7 OD 1.7 to 2.2 OD1.7 and 2.2 OD
• 316L tube – ceramic – titanium tube isolator
• Diameter transition of tube• OD can be reduced• Length ok• Can be encapsulated• Need to better understand
purpose of covers.
• Attempt to make simplified, similar item using brazed ceramic • Material type?• Reduce size
• Ti to Ti joining preferred as simpler
• OD/ID v working pressure• Volume / Quantity required to
fit with new programme?• Services mock up?• Introduce to prototype
staves.
2.5 1.7